Exact and Heuristic Approaches to Middle and Last Mile Logistics

Abstract

Logistics is a well-studied field in operations research. Numerous authors have done extensive work in this area, especially in the domain of routing problems. However there are still aspects of routing to be better explored. For example, routing considering different types of uncertainties, penalties, or multiple objectives in middle and last mile delivery. The main focus of this research is to develop an optimization methodology that improves middle and last mile distribution, maximizing the accessibility of goods to the final customer. This research considers the impact of uncertainty as well as multiple objectives to inform decision makers during route planning. It develops optimization models and methods that solve middle and last mile distribution while considering uncertainty and multiple objectives, thereby, providing a strategic plan that is well-positioned to improve the accessibility of goods to the final customer. Finally, this research is motivated by two realistic applications, vaccine distribution in Africa and improvement of planning for delivery routes and product distribution for commercial companies. This research adapts and generalizes a Vehicle Routing and Scheduling Algorithm (VeRSA) that embeds a heuristic in an exact method to address the need for fast and efficient computation while maintaining information on an optimality gap.